Many people are unaware the Blue Ridge contains remnants of volcanic explosions and lava flows that once erupted and buried part of southwestern Virginia as well as glacial deposits from a 500 million year old Ice Age, and rhythmite, an unusual, maroon bedrock, preserving seasonal variations in ancient lakes and seas. Plus, you can find the oldest rocks in Virginia (the Cranberry gneiss) -- over a billion years old.

During the Ice Age, the upper slopes of mountains had many bare rock slopes. The intense freeze-and-thaw cracked open the sandstone bedrock and produced a jumble of car-sized blocks of rock. These block fields extended for miles along the upper slopes of many mountains. After the Ice Age, with the return to a warmer climate, the forest cover was gradually established over most of the barren block fields.

Today, several remnants of these Ice Age block fields survive on the forests. Travelers in Interstate 81, between I-66 and I-64, can see these Ice Age block fields along the western slopes of Massanutten Mountain and the Blue Ridge.

The Forests include part of the limestone karst terrain (caves, sinkholes, and disappearing streams) for which Virginia and West Virginia are famous. Visitors to the Trout Pond recreation area on the Lee Ranger District can see several sinkholes, a disappearing stream, and the only natural lake in West Virginia.

Ancient giant landslides discovered on the Forests in the 1980s are the largest known in eastern North America. The landslides contain more than one billion cubic yards of rock, and extend more than 10 miles along Sinking Creek Mountain on the New Castle and Blacksburg ranger districts.

The Great Valley, part of the Ridge and Valley Province, extends over 1,200 miles from New York to Alabama. In Virginia, Massanutten Mountain rises 1,000 feet above the Great Valley and extends for 50 miles. The history of this mountain, from ancient sea floor to modern mountain, is told along the Massanutten Mountain Story Trail on the Lee Ranger District. Forest visitors can also stop at the Woodstock Observation Tower for a view of the Great Valley, including the Seven Bends of the North Fork Shenandoah River at the foot of Massanutten Mountain.

Fossils found in the forests include fossil plants and ripple marks and worm borrows in a 500 million year old beach.